


Life's Little Lessons

by Inarchem



Category: Kingdom Hearts
Genre: Braig and Aeleus "Keep" the Peace, Kindergarten AU, M/M, Naminé is Half-French, Ornery Teacher Isa, Single Mom Arlene, Single Parent Lea, Xion Being the Shining Jewel That She Is
Language: English
Status: Completed
Published: 2019-05-24
Updated: 2019-05-24
Packaged: 2020-03-13 10:50:25
Rating: General Audiences
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 3,786
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18939433
Author URL: https://archiveofourown.org/users/Inarchem/pseuds/Inarchem
Summary: Despite what some people may believe, Isa loves his job as a kindergarten teacher, especially when it comes to his favorite student Xion. There's only one problem. Her father.





	Life's Little Lessons

Isa didn’t often strike others as the nurturing type. His no-nonsense attitude tended to fend off whoever made it past his sharp sense of humor. But somehow, Isa had grown to be one of the better kindergarten teachers at Radiant Garden Elementary. He was in his seventh year of teaching now, and things were finally starting to become more predictable. Overly concerned parents, children just learning how to make their first friends— it felt _right_ to work there and lend his hand. However, there was one matter– or person, he should say– that no matter of preparation could brace him for. 

“Hey kiddo!” 

Isa narrowed his eyes. Speak of the devil.

“Dad!” a little voice suddenly called out. With the sound of small feet padding on the ground, Xion raced across the room to greet her father, who was already stooping down to lift her up into his arms. 

“Hey little lady!” Lea laughed, pressing kisses to her brow. “I got off work early, how’s that for a surprise? Think we should get some ice cream to celebrate?”

Isa had to hold back the murderous glare that crept across his face. As cute as she was, Xion’s excited shouting was waking up the rest of the napping class. Snapping his book shut, Isa inhaled deeply through his nose. “Excuse me,” Isa said, quickly walking to the pair, “But if you’re going to leave, you should do it before you wake the entire classroom.” And if his tone was a tad sharper than usual, that wasn’t Isa’s fault.

Lea at least had the decency to look embarrassed there. Scratching the back of his head, he grinned apologetically. “Sorry about that. Guess I got too excited.” 

Isa huffed, but busied himself by kneeling down to help Xion put on her backpack. “It’s nothing. Go on and enjoy the rest of your afternoon. I’ll see you again on Monday, Xion,” he said, his tone turning gentler as he smiled at her. 

Lea’s face seemed to grow red at that, his face almost matching his hair. “Yeah… Uh, yeah, let’s go kiddo!” 

Thankfully, at least Xion seemed to realize that she needed to be quieter than her father and waved goodbye to Isa, giggling softly as Lea put her on his shoulders. 

Waving back to Xion, Isa found himself smiling despite himself. As much of a headache as Lea could be, his daughter was very well-behaved for her age. He would miss having her in his class, after this year was done. In the meantime, the only issue was the matter of Lea Sinclair being her father. 

At first, when Isa had seen Lea walk through his door, he had almost not believed his eyes. But there he was, looking every bit as bright as he remembered. The years had suited him, Isa had thought, stunned. Lea certainly could no longer be described as awkward or gangly. But he still had that same ridiculous smile that Isa remembered as a boy. In his mind, there was an echo of a promise, half-forgotten until now. And before he could stop it, Isa’s heart has immediately given him away by skipping a beat, dratted thing. It was almost as if no time had passed since they were children themselves, except now Lea held a little girl with black hair and a smile as wide as his own. 

For a moment, a tentative smile had gathered at his lips as he moved forward, extending his hand to Lea. Maybe this was the chance to rekindle an old friendship? Perhaps they still had time to fulfill their old childhood promise? But those hopes came to a screeching halt with eight short words. 

_“Hi, I’m Lea Sinclair. Nice to meet you.”_

Isa had felt his heart drop almost immediately. He and Lea had not kept up through the years, but… still the words stung. Of course. Lea didn’t remember him. Why would he? It had been years since they had spoken, let alone seen each other. So Isa had masked whatever hurt he felt and shaken Lea’s hand as a stranger, not daring to say anything more. And although that encounter had left Isa with a bitter sting in his heart, the blow had been somewhat softened by Lea’s daughter, who never let a day pass without giving Isa a drawing, a hug, or some other adorable nonsense.

Feeling a smile soften his expression at those memories, Isa shook his head as he tried to clear his mind. He needed to focus on the other children instead. Their parents would be coming to pick them up soon as well, and that would bring its own brand of chaos. 

The days passed quickly enough in this same manner, but the children in his class ensured that it never became boring. After a few weeks, Isa was struck yet again by how quickly the kids settled in to the classroom routine. But that was just to be expected as they grew used to sharing spaces and making friends. He was proud of the kids and the way they handled these new changes.

Which is more than he could say for most of their parents. 

“Lea again? What has you whining about him this time?” Braig sneered, tapping on the megaphone on his side. He, Aeleus, and Isa all sat together on a bench overlooking the playground, watching as their collective classes ran amok. 

“What’s _not_ to whine about?” Isa said, trying not to look _too_ surly as some of the kids ran past them. 

“He tries,” Aeleus interjected, “That’s a lot more than other parents do.”

Isa scoffed. “Just barely. I knew him when we were children. Attended school with him, and graduated high school with him. I don’t see how that boy can be a father.”

The look Aeleus gave him made Isa feel as small as the children they were watching in that moment. “It’s hardly a basis to judge the man as a parent today. I thought you had better sense than that, Matheson.”

Isa looked away sullenly, tapping his fingers against his thermos. “... Maybe it was. But then again, maybe I’m right for once. Think about it. If Lea is such a successful individual, then where is Xion’s mother?” Jealousy burned low in his stomach. He sighed. “When we were children, he always made a point to remember everyone. He even promised to remember me, no matter how old we grew. It was a child’s promise, but… I suppose I hoped he would keep it.” Isa paused to sip tea from his thermos. “He’s changed. And I don’t know just yet if it’s all been for the better. If it was, then Xion’s mother would still be here.”

Braig gave a low whistle. “Wow, Matheson. Might want to consider getting a hobby, because if you’re building grudges like that, you’ve got too much time on your hands.” Aeleus sighed, opening his mouth as if he was about say something— before immediately snapping his eyes at something over Isa’s shoulder.

“Hold on, sheriff, I got it covered,” Braig smirked, pulling the megaphone to his mouth. _“Vanitas_ , put that down or you’ll be eating it!”

Looking behind, Isa had to bite down a small smirk as he saw a familiar boy with spiky black hair pout as he dropped a blob of mud that had obviously been aimed at his brother Ventus. “Still in charge of the masses?” he murmured. 

“Only when they let me,” Braig chuckled, standing up and stretching his back. “Good thing the little tykes don’t know how to strategize. If they all came at me at once, I wouldn’t stand a chance.” Shaking his head, Isa looked up at him in vague annoyance as Braig clapped on the shoulder. “Give Sinclair a chance before you unleash the full force of your wrath upon him. After all, if he helped raise that little ball of sunshine, he can’t possibly be as bad as you think.”

Isa rolled his eyes at that, but didn’t provoke either teacher any further. If they both saw some worth in giving Lea a second chance, then maybe Isa needed to listen.

And in his defense, that was completely his intention...

Days later, far later in the day than he would have preferred, Isa’s eyes flicked over to Xion, who was busy playing with Naminé. Lea still hadn’t arrived to pick her up, and no one had been able to get in touch with him. It took a greater effort than normal to hide the displeasure from his face, but if Lea wasn’t going to be there, Isa had to at least help Xion smile while she waited. Thankfully, he wasn't alone. Naminé's mother Arlene also sat nearby, tapping impatiently on her cellphone. Due to Arlene’s late work schedule, Naminé was usually the last one to be picked up. However, Naminé couldn’t stand leaving one of her best friends by herself, so she had begged her mother to allow her to help Xion with a last puzzle while she waited for Lea. Admittedly, Isa was grateful for the distraction that Naminé provided for Xion while the rain poured outside. 

“What piece do you think goes next?” Isa asked gently. Xion gave a low hum in thought, before Namine gave a giggle and pointed at a nearby fragment. 

Covering her mouth, Arlene have an exaggerated yawn and stood from the child size chair. “Alright you, it’s time for us to go.”

 _“Maman_ , can we _please_ stay with Xion and Mr. Matheson just a little longer?” Naminé murmured softly, looking up at her mother with soft, blue eyes. “Her papa will be here soon!”

“Sorry, but we’ve already waited long enough for that slacker,” Arlene drawled, sliding her phone in her pocket as she stood. “No offense, Xion.” To her credit, Xion just shrugged, simply pointing for the next puzzle for Isa to pull down. Arlene clicked her tongue, raising an eyebrow at him. “Hope you don’t have to stick around too much longer. Now come on Naminé, _Maman_ has to make dinner tonight.”

Naminé pouted for a moment but nonetheless listened, putting on her yellow raincoat and taking her mother’s hand. “Bye Xion! See you tomorrow!” she called over her shoulder. The words were hardly out of her mouth before a drenched, red-haired blur burst into the room. 

“Hey little lady!” Lea beamed at Xion, hardly paying any attention to the two girls he nearly bowled over, getting a nasty look from Arlene for his trouble. Isa narrowed his eyes at Lea, who was currently chattering away to his daughter. He didn’t even have the decency to look embarrassed, Isa thought bitterly. In fact, he almost looked gleeful at being so horrendously late. But Lea continued to ramble, a giddy smile on his face. “I got a phone call, but then my battery died! Insane, right?!” Quickly, he knelt by Xion, trying to help her put on her backpack. “C’mon Xi’, let’s go! I’ve got a surprise for you!” 

Isa knew that he should just keep his mouth shut and let this go. Nothing good could come of confrontation, especially now. At least Lea had returned, he told himself, trying to calm down. But just looking at Lea’s oblivious, grinning face made something inside Isa _snap_. Before he knew it, he had stomped up to Lea, teeth nearly bared.

“Is this some kind of joke to you?” he hissed, careful to keep his voice low. “We didn’t know where you _were_.” 

Lea’s smile dropped at that, his eyebrows furrowing slightly. “Look, I’m sorry. This is a one-time offence, and it won’t happen again, cross my heart.” 

“Xion _waited_ for you. Do her a favor and pretend you didn’t forget about her, hm? A child should be spared from that much at least.” 

Instantaneously, Lea’s eyes seemed to light up with fury, and for a moment, Isa thought that Lea might strike him. But the moment passed, and instead, Lea breezed past Isa, holding his daughter’s hand. “C’mon Xion, we’re leaving, okay? Say bye to your teacher.” 

Xion frowned at that, looking between her father and her teacher. “But Dad—” A sharp look from Lea silenced her though, and Xion gave a small sigh, leaving with him without another word. But as Isa turned to watch them go, a faint sense of guilt began to build in his chest. As he was about to step after Lea though, he suddenly became aware of another figure standing by the door, watching Xion and Lea leave as well before turning towards Isa.

“Mr. Matheson,” Principal Ansem said, “Could I see you in my office for a moment?” Not waiting for a response, Ansem stepped ahead and slipped back into the hallway.

Isa sighed and slumped against the wall, hitting his head against the cool surface. He exhaled once deeply through his nose. 

_“Shit.”_

He stayed there for a few moments, trying to compose himself or at least think of a half-decent argument to defend himself. But all he could do was think of the look Lea has thrown at him. Maybe it was better that Lea didn’t recognize him—at least he didn’t know now that his childhood friend was some kind of asshole. Shaking his head, Isa ran his hand through his hair, knowing that there was no delaying the inevitable. Still, when Isa sat himself across from Ansem’s desk, he felt very much like a child about to be disciplined. Ansem sat there, steepling his fingers together before heaving a sigh. “I couldn’t help but overhear your words to Mr. Sinclair,” he started, “Which means his daughter most likely heard them too. I’m surprised Isa, you usually have better control than this. What made you behave like that?”

Isa’s hands clenched reflexively in his lap. “He was late,” he sniffed disdainfully, “And he—”

“Apologized. Just like any other parent would. And don’t you teach children how to accept apologies graciously?”

Isa clenched his teeth, growing more furious by the moment that _he_ was the one being chastised. “I don’t understand,” he growled out, “He’s done nothing but shirk responsibility, and _I’m_ the one who’s sitting here?” 

Ansem paused for a moment, drumming his fingers against the desk. And while Isa’s fists remained tightly clenched in his lap, he felt a growing sense of dread as he waited. How many times would he dig his own grave today?

“She’s a twin, you know,” Ansem finally said, levelling a serene look at him. Looking over to him, Isa cocked his head in curiosity. “Xion’s brother, Roxas, was released from the hospital today. Mr. Sinclair was telling me that he just received a phone call from the hospital, and that he wanted to enroll Roxas in the same class as his sister.” Ansem sighed, steepling his fingers over his desk. “Roxas’s coma was originally induced, but… he remained asleep for almost a year. The parents didn’t make it, and Lea stepped in where no one else would.” Ansem turned towards Isa, fixing him with a particularly stern look. “He may not hold up to your clearly superior standards, but he is _trying_. You shouldn’t have been so hard on him. He’s changed his life for these children, and that deserves respect.” 

Isa looked away at that, feeling his cheeks burn with embarrassment. “I… I didn’t know.”

“Did you ever ask?” Sighing, Ansem stood from his desk and clapped a hand on Isa’s shoulder. “I’m not saying this to admonish you. Simply bear in mind that some families face more hardships than others.” 

Isa was silent at that. He had always assumed that Lea had grown to be some kind of slacker, and this new discovery shattered all of that. And no matter how Isa tried to justify himself, he knew that he had been an ass, plain and simple. More than that, he knew he would be a hypocrite if he didn’t go and apologize to Lea for his behavior. 

But Isa only felt worse the next day when he received a notification that Xion wouldn’t be coming to class for the next week. Of course, he knew now that she and Lea must be preparing to bring Roxas home, but Isa couldn’t get the cold look Lea had given him out of his head. He now knew Lea was a parent that cared about his kids. Not only that, but that Lea had sacrificed his freedom to make sure that Xion had a home while waiting for her brother to wake up. 

Guilt and regret churned in Isa’s stomach as he encouraged his class to make cards for Xion’s brother. He knew he needed to apologize, but his lips felt glued shut. Where would he even begin? Even with his class distracted, Isa’s mind roiled. He felt the same cowardliness that silenced him when Lea had failed to recognize him. Isa knew that he deserved that look. He just wished he knew what he needed to do to make things _right._

As it turned out, that opportunity came sooner than Isa thought. Specifically, as he was wandering the grocery store, and a small body crashed into the back of his legs. Luckily, a long time spent working with children made him more than desensitized to ambushes. Slowly looking over his shoulder to make sure the child was alright, his eyebrows show up when he recognized the child. Xion grinned up at him, arms wound tightly around his legs. “Found you, Mr. Isa!”

“So you did,” Isa replied, smiling down at her. “Are you shopping with your family?”

Xion nodded enthusiastically, stepping aside to look up better at him. But before she could reply, there was the sound of a rolling cart squeaking sharply around the corner.

“Xion!” a familiar voice called out, making Isa flinch. “You can’t just run off like that, you—” The words came to a halt, as Isa saw a familiar redhead clutching the hand of an unfamiliar blond boy who looked to be around the same age as Xion. Hesitantly raising his eyes, Isa met Lea’s surprised expression that quickly coalesced into something politely terse. “I see you found your teacher.”

Xion beamed at Lea and pulled Isa over by the hand. “He’s Roxas’s teacher now too, Dad!” Looking over at Isa, she pointed over at the blond who seemed content to be glowering at him from beside Lea. “Roxas, say hi to Mr. Isa! His real name is Mr. Math— Math’son, but that’s too hard to say sometimes, so he says we can just call him Mr. Isa!” 

Waving at Roxas with a small smile, Isa knelt down to his level and offered a hand. “Nice to meet you, Roxas. I hear you’ll be in my class soon with Xion?” Roxas gave his hand a hard stare though before shuffling back behind Lea with a humph. Isa only gave a small laugh though as he stood back up.

“It looks like my infamy has preceded me,” he said, before flicking his eyes back towards Lea. “... My deserved infamy, granted.” 

But judging by the skeptical look that Lea aimed at him though, the man wasn’t ready to make nice with Isa just yet. 

“So,” Lea began, “Ansem mentioned that he updated you about my situation.” 

Isa swallowed. It appeared they were going to have this conversation _now_. “He may have thrown around some… details.”

“Uh-huh. Well, look,” Lea muttered, fidgeting as he crossed his arms. “I’m not looking for a pity party here, got it? I just… Xion and Roxas needed a home, and I knew their parents. So don’t go chewing me out before giving me a chance first,” Lea said, emphatically stabbing his finger in Isa’s chest. “Got it?”

“... I… yes. Got it,” he replied, giving a soft sigh. “But I would like to apologize regardless, to both you and Xion. And to you too Roxas, if you would like it,” he said, sparing a quick glance towards the toddler that still glared silently up at him from his father’s side. “What I said that day was cruel and unwarranted. From what I understand, you’ve… given up a lot when you didn’t have to. I should have known better than to talk to you like that. I’m sorry, to all three of you, and I hope you can forgive me,” he said softly. 

There was a beat of silence, and then Isa felt a small tugging on his hand. Looking down, he saw Roxas staring up at him, his expression somewhat softened. “Dad says we should always accept apologies,” Roxas murmured thoughtfully, before fixing another fierce look at Isa. “But don’t do that again!”

“Roxas!” Lea exclaimed with a disbelieving laugh. “Don’t be rude!” 

“No, it’s alright,” Isa chuckled, “I promise, Roxas, I’ll do my best not to repeat my mistake.” Roxas gave an approving nod at that, seemingly satisfied for now. 

“Seems like you passed Roxas’s test,” he said, ruffling the boy’s hair. “But thank you. The kids and I appreciate you making that effort. You really haven’t changed since we were kids.” 

Isa’s eyes snapped up at that, shock evident on his face. “What?”

“Oh yeah, that’s right, you don’t remember,” Lea laughed nervously, scratching the back of his head. “We used to go to school together. It’s been ages, but I recognized you immediately when I came over on Xion’s first day. But… you didn’t say anything, and I felt that I would be embarrassing myself. Which saying that now only makes things even more embarrassing, huh?” 

Isa could feel a blush slowly growing over his face, as a smile rose to his lips. “N-Not at all. I…” His voice broke with a soft gush of laughter. “To be honest, I thought you had forgotten me." 

Lea snorted at that. "Are you serious? How could I ever forget you?! Sounds like age hasn't make you wiser, Isa," he smirked, green eyes shining. 

"Maybe not," Isa replied, his heart beating quickly in a renewed hope. "But they _have_ made me a better cook." He paused for a moment before cautiously flicking his eyes at Lea. “If you would like, I could bring dinner one night. It’s not much, but… if you’re making food for three now, it might help.” 

“Well, I won’t lie, that would be appreciated,” Lea grinned before his face suddenly grew much more serious. “But there’s only one condition.” 

“Yes, of course. What is it?”

Lea leaned forward, the serious expression staying for only a moment longer before his mischievous grin returned. “If you make dinner, you’re going to have to join us in eating it.”

Isa couldn’t help but return Lea’s grin at that. “I think… I can manage that.”

**Author's Note:**

> Thank you for reading! Also thank you to @victoryatdawn for beta-ing this fic! If you'd like to chitchat, find me on twitter @saixualhealing.


End file.
